What is immutable infra and how to deploy it.

1. Immutable
Infrastructure
Kashif Razzaqui @kashifrazzaqui

2. What is our typical
infrastructure
Pets
Every server has a name and you
have a relationship
Change anything in-place
Automation is optional
Testing is critical; implicit
Susceptible to drift
Difficult to revert state
Slow to recover from disaster

3. Mutable Infrastructure

4. What is immutable
infrastructure
Cattle
No hard decisions
Recreate on change
Automation is compulsory
Testing is optional, different

5. Advantages
Can’t drift
Fast recovery from disaster
Easy to revert
Easy to scale
Perfect staging environments
Self documenting

6. Replace not repair

7. Immutable infra @ Kayako
A case study

8. Context
● Kayako is a helpdesk, like Zendesk and Freshdesk
● Tickets for servers at Softlayer
● Chef, SSH
● Many types of servers and components
● Fragile

9. Not a small toy
example - real
business, real servers

10. ● How do we provision a machine?
● How do we connect various parts?
● How do we release?
● How can we keep costs in control?
● Where have all the services gone?
● Who has access?
How do you do this
with immutability?
Key Questions

11. Tools

12. Tooling
Build Provision Secure Run Connect

13. ● How do we provision a machine?
● How do we connect various parts?
● How do we release?
● How can we keep costs in control?
● Where have all the services gone?
● Who has access?
How do you do this
with immutability?
Key Questions Again

14. Provisioning a machine
Starts out fine … never ends well

15. ● Moved to AWS
● Hardware, network and managed services provisioned with
Terraform
● Software provisioned with Packer
● Infrastructure as code
How do we provision a machine ?

16. How do we connect
various parts?
● Terraform describes the infrastructure as
code
● Integrates well with packer and AMIs
● Even works across cloud providers
● Modular
● Preview changes, apply safely

17. Make anything but with standard parts

18. Easy Modules

19. Lego like

20. How do we
release code?

21. Blue Green Deployment

22. How do we release code?
● Release gets converted to images by Packer
● Terraform makes new servers with new code
● Consul+Nomad orchestrate to switch traffic (canary also supported)
● Terraform takes down old infrastructure
● Rollback is another release OR a nomad task if it was a canary

23. How can we keep costs in control?
● Nomad optimizes workload for utilization and efficiency
● Easily possible to create infrastructure only on demand (day, night)
● Docker compatible

24. ● Consul
○ Dynamic Service Discovery (DNS + HTTP)
○ Service Health
○ Runtime configuration and orchestration
○ Advanced networking
Where have all the services gone ?

25. Who has access?
● Tool chain
○ SREs
● SSH
○ No one
● Secret management and delivery
○ Vault

26. Immutable Infrastructure
Build Provision Secure Run Connect

27. Questions
@kashifrazzaqui
https://medium.com/@kashifrazzaqui